This invention relates generally to running and setting tools for use in connection with locating well packers and the like in well bores. More particularly, but not by way of limitation, this invention relates to a hydraulically operated running and setting tool for use in connection with the positioning and actuation of well packers in well bores and the like.
In the completion and treatment of oil and gas wells and the like, it is frequently necessary to locate a packer in the bore to separate or isolate various zones of the well. It is sometimes desirable or necessary to run the packer into the well bore, set it at the appropriate location, and remove the setting device from the packer and from the well. Such apparatus is illustrated in U.S. Pat. No. 4,516,634, issued May 14, 1985 to Glenn E. Pitts.
The '634 patent illustrates a running and setting tool for well packers that is extended into the well to locate the packer therein and utilizes hydraulic pressures to set the packer at the desired location. After the packer has been set, the setting tool can be released from the packer and withdrawn from the well.
Tools exemplified by the '634 patent operate generally satisfactorily. However, when the well bore below the packer is filled with liquid, difficulty is sometimes encountered since such liquid is substantially incompressible. The manipulation of such setting tools often requires downward movement of a portion of the tool against the liquid column. When this is the case, the incompressible liquid will prevent the downward movement necessary to effect the setting of the packer.
An object of this invention is to provide an improved hydraulic running and setting tool for packers that can be set in the well bore even in the presence of a solid column of liquid located in the well below the packer.